Trunk Overview

A trunk is a telephone line that connects your PBX to the users in the external world. This topic gives an overview of various trunks supported on the Yeastar P-Series PBX System and describes status of different trunks.

Trunk types

The following table shows supported trunk types on Yeastar P-Series PBX System.


Category	Trunk Type	Requirement
SIP Trunk	SIP Register Trunk	No additional telephony module is required.
	SIP Peer Trunk
	SIP Account Trunk
	WebRTC Trunk
Analog Trunk	FXO	SO module or O2 module.
Cellular Trunk	GSM	GSM module.
	3G	3G module.
	4G LTE	4G LTE module.
ISDN E1/T1/J1	E1	EX30 expansion board. Note: E1/T1/J1 trunk is only supported on Yeastar P560 and P570.
	T1
	J1
ISDN BRI	BRI	B2 module.

Trunk status

SIP Trunk status


Status	Description
	Disabled.
	Unreachable.
	Registration failed. Authentication failed. Transport type inconsistent. Rejected.
	Registering.
	Registered.
	Unmonitored.
	Busy. Maximum channels reached.

FXO Trunk status


Status	Description
	Failure: Malfunction in FXO interface, please examine the relevant interface and module.
	Unavailable: No PSTN line plugged in FXO interface.
	Available.
	Busy.

GSM/3G/4G LTE Trunk status


Status	Description
	Failure: Malfunction in module, please examine the relevant module.
	Unavailable: The module is powered off.
	Unavailable: No SIM card inserted.
	Unavailable: No signal.
	Unavailable: PIN/PUK error.
	Unavailable: Cellular network registration failed. Note: Try to manually select the correct carrier setting to fix this issue.
	Available, the icon shows the signal strength.
	Busy, the icon shows the signal strength.

E1/T1/J1 Trunk status


Status	Description
	Failure. It may be caused by the following problems on Physical layer: Malfunction in interface/module. Check the relevant interface/module. No trunk plugged in. Service provider doesn't activate the trunk.
	Failure. It may caused by the following problems on Data Link layer: Incorrect protocol layer configuration. Service provider doesn't activate the trunk.
	Available.

BRI Trunk status


Status	Description
	Failure. It may caused by the following problems on Physical layer: Malfunction in interface/module. Check the relevant interface/module. No trunk plugged in. Service provider doesn't activate the trunk.
	Failure. It may caused by the following problems on Data Link layer: Incorrect protocol layer configuration. Service provider doesn't activate the trunk.
	Available.